摘要:

AbstractThree three‐year‐old Rocky Mountain mule deer were studied for a year to determine the role of skeletal mineral in antler growth. Costal biopsy material, which was obtained at four‐week intervals, was analyzed histologically and histometrically. There was a cyclic mobilization of costal cortical bone during antler growth despite the dietary access to high quantities of elements essential for bone development. Following antler growth the ribs returned to a stable configuration with few resorption spaces. Corresponding to the period of possible weakening from the internal remodeling, there also appeared to be a thickening of the cortical bone by circumferential lamellar addition. Acyclic physiological osteoporosiswas pro

ISSN:0003-276X    

DOI:10.1002/ar.1091620401

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractIn an attempt to support the morphological data indicating a cyclic physiological osteoporosis in three three‐year‐old captive Rocky Mountain mule deer, costal cortical biopsy material was analyzed by densitometric and chemical methods. Bone densities, amount of ash per unit volume and levels of calcium, phosphorus and magnesium per unit volume indicated bone mineral was mobilized during periods of antler growth. However, calcium to phosphorus ratios were maintained at normal levels during this reversible cyclic phenomenon. These data substantiated the morphological observation of acyclic physiological osteoporosisin the mule d

ISSN:0003-276X    

DOI:10.1002/ar.1091620402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractNeurosecretory material in the supraoptico‐hypophyseal tract of 151 hibernating and summer bats (Myotis lucifugus lucifugus) was studied in chromealum‐hematoxylin‐phloxine‐stained serial sagittal sections. Seasonal variations of neurosecretory content throughout the hibernating period (mid‐September through mid‐May) and “active” summer period (June to mid‐September) were observed and the staining density of the neurosecretory material in the supraoptic nucleus, infundibular stem and pars nervosa was “quantitated” visually. Cell counts and measurements also were made to determine if cell number and size changes accompanied seasonal changes in neurosecretory content.A significantly greater staining density of neurosecretory material in the supraoptico‐hypophyseal tract of the hibernating bats, than in the “active” animals was observed. These differences were always greater in the infundibular stem than in the supraoptic nucleus and pars nervosa. Although there was no correlation between seasonal activity and the total number of neurosecretory cells in each brain, there was always a smaller number of dark‐staining cells in the “active” bats than in those that were hibernating. Nucleocytoplasmic ratios of hibernating bats were below those of the active animals. These resulted from smaller nuclear and larger cytoplasmic sizes during hibernation than in the summer. Nucleolar sizes, however, were slightly greater in the hibernating bats than in the active animals. The significance of these results in terms

ISSN:0003-276X    

DOI:10.1002/ar.1091620403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractIn cats, rats and mice the diaphragm possesses an intrinsic plexus of nerve fibres which are concentrated in a narrow band situated approximately halfway between the edge of the central tendon and the peripheral attachment of the musculature. Contributions to the plexus originate in both phrenic and lower six intercostal nerves and both possess three categories of fibres. The first is composed of unmyelinated fibres which ramify on the walls of companion vessels. The second comprises myelinated fibres ranging from 6–10 μ in diameter and these have been classified as afferent components. The third category, forming the major part of the phrenic outflow but only a minor part of intercostal contributions, comprises inyelinated fibres which range from 10–16 μ in diameter and possess preterminal expansions. Phrenic fibres of the third category have been identified as efferent components because they terminate in motor end plates but the function of corresponding intercostal components cannot be defined conclusively.Quantitative studies at three distinct levels within each of ten phrenic nerves in cats, show an increase in the number of myelinated fibres of diameter 12–20 μ in the peripheral third of the nerve. This suggests that the phrenic nerve receives an accession of fibres in its peripher

ISSN:0003-276X    

DOI:10.1002/ar.1091620404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractRats were given single doses of an orally‐active estrogen by mouth on days 1–5 of pregnancy. Examination of uteri on day 8 for implantations revealed that the median effective doses for preventing 50% of the eggs shed from implanting were 0.047, 0.050, 0.035, 0.145 and 0.380 mg/kg for days 1, 2, 3, 4 and 5 respectively. It was found that failure of pregnancy after treatment with the minimal 100% effective dose (ED100) on days 1, 2 or 3 was due to expulsion of eggs from the reproductive tract by day 5. Treatment of rats with the ED100on day 4 caused expulsion of some eggs from the tract by day 5, but also had effects on the uterus: the position of the blastocysts within the lumen was abnormal and their orientation relative to the mesometrial‐anti‐mesometrial axis disturbed. No decidual reaction was observed on day 6 in such rats or on day 9 in pseudopregnant rats treated similarly and subjected to uterine traumatization on day 5. Treatment with ED100on day 5 had no effect on egg transport or on the positioning of blastocysts within the lumen on day 6. A decidual reaction was seen around the blastocyst on day 6, but in pseudopregnant rats treated similarly and subjected to uterine traumatization on day 5 no decidual reaction was found on day 9. The pontamine blue reaction was negative in nearly all rats dosed on day 4 and examined on days 6–8. In rats dosed on day 5, however, the blue reaction was negative on day 6, but positive on day 7, i.e., delayed by 24 hours compared to controls and appearing later than the decidual reaction. The blastocysts were unattached in these rats on day 6, but may have attached briefly on day 7 (suggested by the positive blue reaction) and subsequently failed to develop further owing to disappearance of the decidu

ISSN:0003-276X    

DOI:10.1002/ar.1091620405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractBullfrog larvae with lymph glands removed failed to synthesize antibodies to BSA but they rejected skin allografts normally. Tadpoles with unilaterally removed lymph glands had antisera with detectable titers equivalent to unoperated animals. Lymph glands are composed of macrophages which line sinusoids interposed between cords of lymphoid cells.

ISSN:0003-276X    

DOI:10.1002/ar.1091620406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractPhytohemagglutinin‐P (PHA‐P) exhibited inhibitory action on the growth of two human epithelioid cell lines, HeLa and L‐132, and on the L‐929 strain of mouse fibroblasts. Growth of stationary cultures was measured spectrophotometrically by DNA production after 96 hours incubation. The mitotic indices of the three cell lines were reduced significantly by PHA‐P after 72 hours incubation.Histochemical studies demonstrate depressed production of cytoplasmic RNA in 72‐hour HeLa cultures after treatment with PHA‐P, with the appearance of prominent, PAS‐positive, diastase‐fast granules in the cytoplasm. Bound lipid aggregates increased in amount in the cytoplasm of HeLa cells after PHA‐P treatment. The PAS‐positive, diastase‐fast granules were also found in the cytoplasm of the L‐132 and L‐929 cell lines after treatment, but cytoplasmic RNA remained unchanged qualitatively. Alkaline phosphatase was slight in amount in HeLa cells and was reduced to trace amounts after PHA‐P treatment. L‐132 cells showed moderate to heavy concentration of alkaline phosphatase, which remained unchanged qualitatively after PHA‐P treatment. The enzyme could not be demo

ISSN:0003-276X    

DOI:10.1002/ar.1091620407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractThe cerebral and cerebellar cortices of mice were subjected to a histochemical method for the demonstration of chloride after perfusion fixation with glutaraldehyde. Unfixed, nonasphyxiated cortices subjected to the same chloride method were used as controls. Sections of control material showed a rather uniform chloride distribution in which only the pia and the blood vessels stood out as dark structures containing an appreciable amount of chloride. Sections of glutaraldehyde fixed cerebral cortex showed an accumulation of chloride in apical dendrites. In glutaraldehyde fixed cerebellar cortex the chloride accumulated in the fibers of Bergmann and sometimes in the large dendrites of Purkinje cells. The chloride movement during glutaraldehyde perfusion is in all respects comparable with the movement of chloride caused by asphyxiation of the cerebral and cerebellar cortex.

ISSN:0003-276X    

DOI:10.1002/ar.1091620408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractA quantitative morphological study was made to assess the effects of gonadectomy and hypophysectomy on the pineal in the mouse. Gonadectomy caused a slight increase in the pineal volume whereas hypophysectomy induced a marked decrease. The increase in pineal volume after gonadectomy was associated primarily with slight enlargement of pineal cells in the peripheral area of the gland, and the larger decrease in pineal volume after hypophysectomy correlated with marked atrophy of pineal cells throughout the entire gland.

ISSN:0003-276X    

DOI:10.1002/ar.1091620409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractElectron microscopy of hypertrophic left deltoid muscle of a nineyear‐old female diagnosed with neuro‐ectodermal dysplasia and concomitant muscle hypertrophy was made. Satellite cells, similar in morphology to myoblasts, are found situated apposed to and beneath the basement lamina of muscle fibers. Satellite cells contain mitochondria, granular ER free ribosomes, polysomes and 50–100 Å thick, randomly oriented filaments. Plasmalemmae of apposed satellite and muscle cells show varying numbers of caveolae and degrees of interdigitation similar to plasmalemmae between fusing myoblasts of embryonic muscle. Discontinuities in the muscle fiber plasmalemma and confluence, or overlie, of satellite cell and muscle fiber plasmalemmae are sometimes seen.One possible interpretation of the above evidence suggests that, in this example of muscle hypertrophy, satellite cells may assume myoblast‐like properties and serve as focal points for muscle fiber enlargement during muscle hyp

ISSN:0003-276X    

DOI:10.1002/ar.1091620410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY